Russia's Proton M launch vehicle made its first flight on 7 April, carrying the Ekran-M television satellite into geostationary orbit. The launch of the upgraded Khrunichev Proton K, from the Baikonur Cosmodrome in Kazakhstan, came after technical and financial setbacks had delayed the launch, originally planned for last year. The Ekran satellite successfully separated from the booster's Breeze M upper-stage seven hours after launch.
The Proton M features modifications to increase the payload and reliability of the launch vehicle, with more powerful engines, structural enhancements to support the increased lift capability and a digital guidance system.
The first stage of the launch vehicle features a new version of the RD-253 hypergolic engines, with sea-level thrust increased by 19,800lb (88kN) to 360,000lb. With the standard second and third stages, the Proton M can carry 22t payloads into low Earth orbit, compared with the Proton K's 21t capability. The Proton M includes the Breeze M upper stage. A digital flight control system has replaced the traditional analogue system, allowing more efficient propellant consumption.
The Proton M will join the stable of Lockheed Martin-Khrunichev-Energia joint venture International Launch Services.
Source: Flight International
